Process for obtaining deoxidized copper



, Jan. 6, 1942. R. PERRIN 2,268,615

PROCESS FOR OBTAINING DEOXIDIZED COPPER Filed March 14, 1938 Fave/a Z01,

Patented Jan. @1942 2,288,615 PROCESS FOR. OBTAINING DEOXIDIZED COPPERIten Perrin, Paris, France, assignor to Societe dElectrochimie,dElectrometallurgic et dos Acleries Electriques dUgine,

corporation of France Application March 14,1938, Serial No. 195,841

' In France March 16, 1937 1 Claim. (on. -76) In metallurgy, in order todecompose certain harmful compounds which the metallic baths contain,reactions are often produced between these metallic baths and solidsubstances, but these reactions vary according to the nature of thesolid substance and the metallic bath present.

Paris, France, a

sible in the processes previously known to utilize all the reactingenergy of the solid material in relation to the compounds contained inthe bath upon which it should react. To sum up A solid substance placedin the presence of a v metallic bath-may behave in various ways.

(a) If it is fusible under the conditions of the operation it will fuseas soon as it is brought into contact with the bath, and there will bein fact a reaction between the liquids.

(b) If it is soluble in the bath it will dissolve therein (like forexample carbon in the metallurgy of steel) and it will then act in theliquid state on the element or elements of the metallic bath upon whichit should react. (c) This substance finally may remain solid in thepresence of a metallic bath while reacting on certain compoundscontained in the bath; this is for example the case of carbon broughtinto the presence of oxidized copper.

If in fact the case of oxidized copper is specially considered it is tobe noted that it was already known to treat copper by materialscontaining carbon with the object of obtaining a far-reachingdeoxidation but the reactions utiobtaining chemical equilibrium betweenthe solid material and the compounds to be attacked thereby is long anddifllcult.

With the object of arriving rapidly and economically at this equilibriumby renewing with an accelerated frequency the surface of the contactbetween the bath of metal and the solid reacting material possessing theproperties recalled above, I have proposed according to the lized aregenerally slow and must be eflfected in furnaces.

Thus it has been proposed to improve the contact between copper and thecarboniferous substance to bury the carbon in the body of the copper byfilling completely with-pieces of coke the electric furnace in which theoperation is efiected, but the operation is not rapid, the renewal ofthe contact betweenthe copper and the coke is not suiiicient and it isindispensable in practice to apply external. heat. Moreover it isnecessary to employ considerable quantities of coke which produces anincreased consumption of electrical energy.

The disadvantages cited above are suppressed by utilizing the processaccording to the invention which gives the possibility of efiectingfarreaching and rapid reactions without necessarily employing externalheat between a metallic bath and a solid substance of density less thanthe metal, not dissolving therein and not melting at the temperature ofthe reaction.

The diiiiculties which have been met with up to the present in similartreatments arise precisely from the fact that the solid materialsutilized have a density less than that of the metal, areinsoiubletherein and do not melt at the temperature of the operation. Itis imp s- .present invention to subject the reacting ele- By this meansthe rapidity of the reactions is such that no application of externalheat is necessary. It is important however to explain how thesesuccessive intermixings should beeffected for the success of theoperation. If it is supposed that one of the chambers of the apparatuscontains molten metal upon which the solid reacting-substance has beendropped and that the metal is poured slowly from this chamber into theother chamber, the solid reacting material having a density much lessthan that of the metal remains at the surface of the bath facilitated bythe eddies which are produced from the shock of the molten metal againstthe walls of the chamber into which it is poured.

It is important in all cases that the pouring of the metal with thesolid reacting material should be sufliciently strong for there to bepenetration of the pieces of solid reacting material into the body ofthe metal, which condition is the more diflicult to produce the greaterthe difference between the density of the reacting material and that ofthe metal.

If the reaction between the solid reacting material and the metal givesrise to the production of a solid or liquid substance of low volatilityit is important to pour as rapidly as possible. It is likewise suitablein this case that the solid substance should be introduced preferablyinto the apparatus in a sufllciently divided form for example in theform of little pieces, grains, or even perhaps of powder.

If on the contrary the action of the solid substance on the metal givesrise to a gaseous or very volatile substance precautions should be takenso that the reaction is not active enough to lead to an explosion oreven to expulsion of metal out of the apparatus. Besides the fact thatthe apparatus should be suitably open to permit the outlet of gases asthey are formed two means may be provided for adjusting the activity ofthe reaction.

(1) The movement of the apparatus may be slowed down. It must howeverremain sufliciently rapid for there to be penetration of the solidreacting material into the body of the molten metal, which condition isessential for rapid reaction.

(2) The solid reacting material may be introduced periodically inregulated proportion (at .each .period oi movement for example) or evenin a less divided form. It is of importance not to use too fine powderwhich may be entrained partially by the gases which are evolved.

The adjustment will be effected for each particular treatment byprevious tests.

The process of the invention is capable of being applied in advantageouscondition in an pparatus of thy type represented by way of ampleschematically in the accompanying drawing.

The apparatus comprises two chambers I and 2 relatively deep connectedto one another and communicating with a medial aperture 3 open to theatmosphere. These two chambers are constituted by a metallic casing- 4provided with a refractory lining 5. The whole is mounted on a shaft 6capable of turning in support bearings I and receives a rapidalternating oscillatory movement by means of a suitable drivingmechanism of known type which isnot shown. This movement brings turn byturn each of the cham-- hers I or 2 into a position respectively high orlow and with an inclination such that its contents are projectedenergetically and from the greatest height which the construction of theapparatus permits into the other chamber. This effect may be facilitatedby imparting at first a speed so great that centrifugal :iorce maintainsor tends to maintain charge towards the bottom of the receptacle whichcontains it, and then rapidly decreasing when the bottom or thereceptacle is about to reach or reaches the top of its path. Q

The process and the apparatus described may be applied particularly tothe deoxidation of oxidized copper by utilizing carbon as solid reactingmaterial.

The following is an example of such an-application.

Into an apparatus such as that shown in the drawing 1 metric ton of veryoxidized molten copper was introduced (bran grain copper containing 1.1%of oxygen). At the same time 5 kgs. of charcoal previously heated wereadded and several oscillations were eflected. At each pouring anenergetic intermixing and a very active ebullition are produced;Continuing the oscillations of the apparatus 800. gms. or charcoal willbe added every fourth oscillation. At the end of a few minutes theoxygen content had fallen to 0.02%. The copper remained molten.

What I claim is:

A process for quickly and regularly obtaining I copper very low inoxygen from oxidized copper by means of successive simultaneous andviolent pourings of fluid copper and charcoal, characterized in that thetotal quota of charcoal necessary for the deoxidizing operation isintroduced in successive portions in the form of charcoal pieces, thesuccession of the introduction of the said portions being regulated soas to correspond to the exhaustion of the action of the precedingportion.

RENE PERRIN.

